The object of the invention is a process intended more specifically for overprinting of already printed packages.
The printing applies especially to corrections, additions, and/or changes on packages.
The invention makes it possible to correct a printing error. It allows a package to be re-used.
These packages to be corrected can be found especially in foodstuffs and large-scale retailing, industry, perfumery, cosmetology, and, finally, pharmacy.
The prior art can be defined by the following patents:
FR.2,739,805: This invention relates to a process designed more specifically for overprinting and consists in blanking, by pad printing, with specific inks, an already printed existing medium for purposes of overprinting a text or a design.
This process comprises the use of pad printing machines in an automated context. The media are stored in a distributor, then, according to an electronically managed rhythm, are taken by a conveyor to an automatic printer. At this stage, the media are positioned on various printing and heating stations for purposes of their overprinting. When the media have undergone all the different phases of the operation, they are discharged into a container in which they are counted.
FR.2,790,996: This process comprises the use of pad printing machines in an automated context. The media are stored in a supply cart. Then, using a manipulator arm, the media are positioned on various printing heads to be overprinted. When the media have undergone all the different phases of the operation, they are discharged onto the removal plane where they are manipulated by the operators.
WO 03 093379: The invention relates to a covering composition used as a veneer covering that contains an alkyd resin, with an average molecular mass of between roughly 500 and 2,000, and with polydispersivity of less than roughly 2. Once rebaked, this composition is essentially stable from the standpoint of color. It is essentially flexible and can be used as a veneer on a container body. The invention likewise relates to a substrate covered by said composition.
JP 2001 232980: Problem to be resolved: To provide an overprinted card of low cost and a production method in which the cost of materials is reduced and in which the production rate of the overprinted cards is improved.
Solution: In the overprinted card composed of a center part, an upper part, a magnetic card, a closing layer, a print layer, and a protective layer, it is specified that the center part 11 is a white, opaque sheet and the upper sheet 13 is a transparent sheet.
U.S. Pat. No. 6,098,541: Overprinting embosser composed of three print surface retaining portions located facing one another under non-hollow area conditions, each portion of the print surface comprising an expanded thermoplastic sheet attached to each print surface retaining portion, a portion for supporting the print surface retaining portions that can slide rotationally by means of a generally movable, resistant hinge, and a guide bar for guiding the direction of the sliding portions. Moreover, so as to control the position in which the sliding portions are stopped such that each print surface portion is positioned at a predetermined printing position, there are three grooves on the guide bar, and a spring with a projection corresponding to said grooves is fixed on the sliding portion.
These different inventions have numerous disadvantages, especially the two inventions described in patents FR.2,739,805 and FR.2,790,996. The overprinting is done by a machine that works rotationally relative to two stations. One station blanks the part to be modified; the other station applies the overprint.
This operation, by a machine with two rotary stations, does not allow production rhythms to be accelerated.
The process and the machine for implementing it can overprint 1000 (thousand) pieces per hour, according to the prior art.